201 results about "Discrete element model" patented technology

The invention discloses a discrete element-based three-dimensional fault / fracture network modeling method and device under a backlash pushing and covering system, and relates to the technical field of three-dimensional fault modeling, and the method comprises the steps: building an initialized fault plane model based on the seismic logging information parameters of a target region; extracting stratum parameters of the target area, and determining a deformation process in combination with an equilibrium profile recovery method; the method comprises the following steps: calibrating mesoscopic parameters of discrete elements according to stratum parameters, depositing a first discrete element model, optimizing and generating a second discrete element model, setting boundary conditions to carry out back-flushing pushing-covering simulation, comparing an output result of the second discrete element model with an actual geological section, adjusting model parameters until the output result and the actual geological section are matched, and establishing a three-dimensional fault and fracture network. And analyzing and establishing spatial distribution characteristics of the target area, and carrying out dynamic evaluation and trend prediction on the activity of the three-dimensional fault. According to the method, the geomechanical model is fused, the subjectivity of manual interpretation is overcome, and the problems of fault tip extension and the like in grid reconstruction are effectively avoided.

The invention provides a discontinuous graded soil large-scale discrete element model generation method. The method comprises the following steps: (1) creating a soil particle material and setting soil intrinsic parameters and contact model mesoscopic parameters; (2) creating a 3D penetrometer geometric model for assisting model hierarchical generation and impact simulation; (3) importing the geometric model into EDEM software; (4) creating a soil particle factory for hierarchically generating the model; (5) generating particles with different scale factors in the soil particle factory; (6) selecting different geometric model combinations for assisting model hierarchical generation in the step (2) to generate a model for simulation; and (7) importing the geometric model of the 3D penetrometer in the step (2) into the model generated in the step (6) to carry out impact penetration dynamics simulation. According to the method, construction of the discontinuous graded soil large-scale discrete element model can be realized, and the problem that effective calculation cannot be carried out due to too many particles of a large-scale model generated by fine-grained soil can be effectively solved.

The invention provides a carbon dioxide phase change blasting numerical simulation method based on an FDEM. The carbon dioxide phase change blasting numerical simulation method comprises the following steps that a carbon dioxide adiabatic expansion p-V relation is determined according to a Span-Wagner fluid model; establishing a finite-discrete element (FDEM) numerical model, and setting a non-reflection boundary; determining mesoscopic parameters in the FDEM model according to the physical and mechanical parameters of the rock mass; and applying a carbon dioxide phase change blasting load, and solving a finite-discrete element (FDEM) model. According to the method, the Span-Wagner fluid model recommended by the American national standard is adopted to replace a traditional ideal gas model to calculate the adiabatic p-V relation of the carbon dioxide, the description of the carbon dioxide pressure is closer to the reality, the value of the FDEM mesoscopic parameter is associated with the physical and mechanical indexes of the rock mass, a theoretical basis is provided, the reasonability of the parameter value is ensured, and the method has the advantages of high reliability and high reliability. Therefore, a carbon dioxide blasting numerical simulation result is close to an actual application result, and the accuracy of the numerical simulation result is improved.

The invention discloses an optical fiber soil body coupling performance simulation method based on discrete elements, which comprises the following steps: step 1, determining size parameters of a test box, the diameter of an optical fiber, the minimum radius and the maximum radius of soil particles, and macromechanical parameters of a test soil body, the size parameters of the test box including length, width and height, and the diameter of the optical fiber; the macromechanical parameters of the test soil body comprise density, cohesion and friction angle; 2, simulating through a two-dimensional particle flow direct shear test to obtain material mesoscopic parameters of the test soil body; 3, generating a three-dimensional drawing discrete element model; and 4, pulling the optical fiber, and observing the force-displacement of the optical fiber in the drawing process, the deformation information of the sample soil body and the cementing failure state of the test soil body. According to the optical fiber soil coupling performance simulation method based on the discrete elements, the problem that an existing continuous medium analysis method is not suitable for discontinuous media is solved.

The invention provides a discrete element simulation method of an implicit particle environment, which comprises the following steps: S1, fully mixing an ore grinding medium and a ground material, taking the mixture as a whole, and measuring a stacking angle; s2, constructing an ore grinding medium discrete element model of implied particles; s3, constructing a discrete element model of the accumulation angle measuring device; and S4, parameter optimization and discrete element simulation. The maximum error between the collision energy spectrum obtained through simulation of the method and conventional simulation is only 3.3%, meanwhile, it is avoided that a large number of mineral particles are added into simulation calculation, a large number of calculation resources are saved, and energy, speed and other information of mutual collision between media in the ore grinding operation process can be rapidly and accurately obtained.

The invention discloses a dangerous rock falling motion feature analysis method based on discrete element simulation, and belongs to the technical field of engineering geology. Comprising the steps that dangerous rock data are collected through multiple means and preprocessed, and a three-dimensional visual dangerous rock mass initial model is constructed; based on the three-dimensional visual dangerous rock mass initial model, constructing a discrete element model, defining contact types and parameters among joint units by adopting a Hertz-mindlin contact theory, and determining normal contact force; based on the discrete element model and the normal contact force, a discrete element simulation technology is adopted, multi-physical field factors are considered to simulate dangerous rock falling movement, a discrete element model simulation result is obtained, a dynamic updating method is adopted for joint failure judgment, and the discrete element model is verified through an indoor physical model test and field monitoring data. And designing and implementing a prevention project according to a simulation result, thereby effectively preventing dangerous rock falling disasters and ensuring project safety.

The invention relates to the technical field of geological structure deformation simulation, in particular to a method and a device for simulating deformation of a basement involved tectonic zone based on discrete elements, and the method comprises the steps: extracting stratum information of a target area through geological survey and seismic data analysis; defining substrate wall conditions according to substrate activity distribution conditions; setting a target speed according to the multi-stage deformation in the target area; based on the geological parameters, determining particle mesoscopic parameters, and constructing a discrete element model; starting the boundary wall and the foundation wall to move, and simulating the dynamic evolution process of the tectonic zone; and when the contraction amount of the rear edge boundary of the motion plate meets a preset condition, acquiring and analyzing a simulation result based on the motion data of the filling particles. According to the method, by simulating and analyzing various basement involving construction modes, controlling the basement speed boundary conditions, simplifying the model calculation amount of the basement, improving the simulation efficiency and enhancing the result reliability, theoretical and technical supports are provided for oil-gas exploration work of the basement involving tectonic zone.

The invention belongs to the technical field of discrete element simulation, and particularly relates to a digital twinborn discrete element model construction method based on CT (Computed Tomography) scanning, which comprises the following three steps of: in a CT scanning stage, acquiring a high-resolution cross-sectional image by optimizing scanning parameters, and carrying out image noise reduction and feature enhancement processing; in the structural analysis stage, a segmentation model is constructed based on a deep convolutional neural network, and automatic annotation of a scanned image and intelligent prediction of a three-dimensional space topological relation are realized; in the discrete element modeling stage, the reconstructed three-dimensional grid model is converted into a discrete element model with real physical attributes through parameter calibration, and discrete element simulation is achieved. According to the method, the non-destructive detection advantage of industrial CT and the feature extraction capacity of deep learning are combined, microstructure characterization is converted into macroscopic performance prediction, and a reliable simulation analysis method is provided for performance optimization of the composite material.

The invention discloses a discrete element contact parameter calibration device and method based on a dynamic repose angle, the device comprises a platform on which a motor and a motor control panel are fixedly arranged, the motor control panel is connected with a PC, the motor control panel is connected with the motor, and an output shaft of the motor is fixedly connected with a driving belt wheel; a first bearing seat and a second bearing seat are installed on the top face of the platform, the first bearing seat is rotationally connected with a first rotating shaft, the first rotating shaft is fixedly connected with a driven belt wheel connected with the driving belt wheel through a belt, and the two ends of the first rotating shaft are fixedly connected with driving wheels respectively. The second bearing seat is rotationally connected with a second rotating shaft; two ends of the second rotating shaft are fixedly connected with supporting wheels respectively; the cylinder is in contact with the surfaces of the driving wheel and the supporting wheel; a high-speed camera connected with a PC (Personal Computer) is fixedly arranged on the top surface of the platform, and discrete element analogue simulation software is installed in the PC. According to the invention, the dynamic angle of repose of the material in different flowing states can be measured in real time, and high-precision calibration of contact parameters among particles is facilitated through a discrete element model.

The present invention discloses a method for evaluating the load transfer behavior of asphalt mixture based on the quantification of force chain characteristics, comprising: (1) establishing a two-dimensional discrete element model of asphalt mixture according to the composition of the asphalt mixture; (2) performing a virtual bearing test on the discrete element model of the asphalt mixture to obtain contact information between aggregates and aggregate information; (3) setting a force chain formation standard according to the contact information between aggregates; (4) identifying the asphalt mixture force chains one by one based on the set force chain formation standard; (5) defining a force chain characteristic quantification index; (6) calculating the force chain characteristic quantification index; (7) evaluating the external load transfer behavior of the asphalt mixture according to the calculation result of the force chain characteristic quantification index; the present invention realizes the accurate evaluation of the load transfer behavior of the asphalt mixture from the perspective of the quantification of force chain characteristics.

The invention provides a root-soil mixture impact penetration sounding dynamic response prediction method. The method comprises the following steps: firstly, constructing a discrete element model of a root-soil mixture, and constructing a root system structure with high simulation characteristics in the discrete element model; and fine simulation of interaction of the root system and the soil particles under the impact penetration power load is realized in combination with a contact model for simulating mechanical properties of the root-soil mixture, so that impact penetration penetration prediction of the root-soil mixture is finally realized. According to the method, various behaviors such as contact, friction, stripping and tearing between root-soil particles can be dynamically simulated on a microcosmic level, the behaviors are coupled into an integral model of impact penetration sounding, and the penetration resistance mechanism of a root-soil mixed medium can be accurately captured through the method, so that the penetration resistance of the root-soil mixed medium is accurately determined. And a reference is provided for abnormal identification and correction of the penetration signal.

The invention discloses a method for analyzing longitudinal force and longitudinal displacement of a long and large ramp continuously welded track under train braking, which comprises the following steps of: establishing an analysis / finite element model of the long and large ramp ballast track continuously welded track, taking initial ballast bed longitudinal resistance as an input parameter, and calculating to obtain initial distribution of longitudinal force and longitudinal displacement of a continuously welded track steel rail; meanwhile, the maximum value of longitudinal displacement of the continuously welded rail is obtained; and establishing a discrete element model of the long and large ramp ballast track seamless track, taking the maximum value of the initial distribution of the longitudinal displacement of the seamless track steel rail as an input condition, carrying out cyclic loading of the long and large ramp ballast track under the loading condition through a longitudinal displacement-longitudinal resistance dual-control method, extracting the longitudinal resistance of a track bed under the non-loading condition, and calculating the maximum value of the longitudinal displacement of the long and large ramp ballast track. And importing the data into the established analysis / finite element model to obtain updated distribution of longitudinal force and longitudinal displacement of the continuously welded rail. According to the method, the evolution characteristics of the longitudinal resistance of the long and large ramp ballast track seamless track ballast bed can be reasonably reflected.

The invention provides a shield hob type selection and tunneling parameter optimization method and device, a terminal and a medium, and belongs to the technical field of shield construction, and the method comprises the steps: obtaining the stratum information of a target project, the selectable type and / or value range of shield hob structure parameters, and the value range of tunneling parameters; constructing a rock mass discrete element model based on stratum information; presetting combinations of multiple groups of tunneling parameters and shield hob structure parameters; aiming at each group of combination, constructing a corresponding hob model, obtaining a rock breaking numerical simulation model based on the hob model and the rock mass discrete element model, inputting the tunneling parameters in the current combination into the rock breaking numerical simulation model for simulation calculation, and obtaining rock breaking specific energy and wear specific energy of the hob; and final shield hob structure parameters and tunneling parameters are determined. According to the method, the rock breaking numerical simulation model is constructed and the simulation calculation is performed, so that the rock breaking specific energy and the wear specific energy of the hob can be obtained, and the hob structure parameters and the tunneling parameters are cooperatively evaluated.

The invention discloses a porous rock two-dimensional numerical model processing method and device, equipment and a medium, and can be applied to the technical field of rock mechanics. The method comprises the following steps: importing a wafer radius and coordinate data of an initial rock sample generated by first software into second software, and obtaining user demand pore feature information including target porosity, target pore size distribution and target pore direction distribution probability; controlling the second software to generate a total wafer set according to the pore feature information required by the user and the wafer radius and coordinate data of the initial rock sample, importing the total pore wafer set into the first software, and then controlling the first software to process the initial rock sample according to the total wafer set, the discrete element model meeting the pore characteristic information required by the user is obtained, and then the mechanical behavior simulation of the porous rock microstructure characteristics is performed according to the discrete element model, so that the accuracy of porous rock simulation can be effectively improved, and the technical cost is reduced.

The invention discloses a selective laser melting simulation method simultaneously considering molten pool and microstructure evolution, which mainly comprises establishment and calculation methods of powder laying and a powder melting and solidification process model, and comprises the following specific steps: setting the geometric dimension and the number of internal crystal grains of a substrate to generate a polycrystalline substrate; establishing a discrete element model, simulating a roll shaft powder spreading process, and obtaining particle information; introducing a sequence parameter, constructing a free energy density functional, and establishing a heat-flow-microstructure strong coupling phase field model; constructing a powder bed geometric model, distributing grain orientation, and dividing grids for the powder bed geometric structure; setting material attributes and boundary conditions, and solving the phase field model by a finite element method; and carrying out visualization processing on a calculation result to obtain a molten pool and a microstructure morphology. Evolution behaviors of the molten pool and the microstructure in the selective laser melting process can be simulated at the same time, alternate simulation and data transmission of the powder laying process and the laser scanning process are achieved, and therefore actual machining production is guided, and technological parameters are optimized.

The invention discloses a frozen soil roadbed thaw collapse and thawing tray evolution discrete element simulation method considering ice-water phase change. The method comprises the following steps: step 1, acquiring frozen soil roadbed parameters; 2, constructing a frozen earth embankment discrete element model; 3, setting material contact parameters; 4, setting a temperature boundary; step 5, thermodynamic coupling of the frozen soil roadbed, including heat transfer and ice-water phase change; step 6, thaw settlement; 7, recording particle distribution; and step 8, melting disc evolution. The device can simulate the heat transfer process of heat from the surface layer of the asphalt pavement to the interior of the permafrost embankment in the sun irradiation process. In the ice-water phase change process, when the heated temperature of ice particles exceeds zero DEG C, the ice particles are melted into water, the bearing capacity of the roadbed is greatly reduced, the thaw collapse of the frozen soil highway roadbed is caused, different influences of a sunny slope and a shady slope on settlement of different monitoring points along an embankment can be calculated, the evolution process of a melting disc in permafrost is simulated, and the method has very high universality.

The invention belongs to the field of mechanical research of natural gas hydrate sediments, and provides a hydrate-containing sediment discrete element model mechanical parameter calibration method, which comprises the following steps: S1, sample preparation and triaxial shear test; s2, respectively constructing discrete element models for the four sediment samples in the step S1; s3, performing staged calibration on mechanical parameters of the sediments with different components; and S4, outputting a discrete element model result. According to the method, four samples are prepared aiming at the muddy silt hydrate-containing sediments, different contact models are adopted according to the mechanical characteristics of different components of the samples, the model complexity is gradually increased from a single component to multiple components through staged calibration, it is ensured that the mechanical behavior of each component can accurately reflect actual experimental data, and the experimental accuracy is improved. Through combination of experiments and numerical simulation, accurate calibration of micromechanical parameters of the muddy silt hydrate-containing sediment discrete element model is realized, and the accuracy of the discrete element model is improved.

The invention discloses a flexible biological and interception model construction method based on particle contact and a simulation device, and the method comprises the steps: carrying out the improved contact model parameter determination based on various parameters of a marine organism according to a discrete element particle contact model of a target marine organism; and the flexible contact model is combined with the particle replacement model to generate a flexible target marine organism discrete element model, a target marine organism group is constructed, and a finite element / discrete element coupling calculation method is utilized to perform simulation evaluation on the interception efficiency of the interception net on the target marine organisms. The discrete element particle contact model combines the characteristics of efficient calculation of discrete elements and flexibility of biological materials, can accurately and quickly simulate and obtain the results of deformation, breakage, escape and the like of marine organisms under the action of the blocking net, and analyzes the interaction mechanism of the blocking net and the marine organisms according to the results. According to the method, the blank of describing the biological material by discrete elements can be filled, and the research on the marine organism intercepting mechanism of the intercepting net is facilitated.

The invention discloses a coal rock seepage-stress coupling simulation calculation method, which belongs to the technical field of geotechnical engineering numerical simulation, and comprises the following steps: carrying out gray threshold division on a coal rock sample CT scanning result to obtain a coal rock CT section; identifying particle position information in a coal rock CT section, and establishing a coal rock refined discrete element model; performing mechanical constitutive parameter calibration on the coal rock refined discrete element model; and on the basis of the coal rock refined discrete element model subjected to constitutive parameter calibration, establishing a fluid grid, setting model parameters, and carrying out seepage-stress coupling calculation. According to the method, the real form, size, spatial distribution and mutual inlaying relation of the mineral components in the coal rock can be accurately captured, and the most real basis is provided for accurate simulation of subsequent mechanical behaviors.

The invention discloses a thermal regeneration asphalt mixture functional reinforcement phase optimization design method based on discrete element simulation in the technical field of thermal regeneration road engineering material optimization, and the method comprises the steps: constructing a discrete element model of an asphalt mixture, extracting skeleton gap characteristic parameters, including the skeleton gap size, the volume ratio and the distribution condition, and obtaining a discrete element model of the asphalt mixture; according to the optimization design method, the mixing amount, the diameter range and the length parameters of the functional reinforcing material are optimized according to the characteristic parameters, the blindness of a traditional experiment depending on experience is avoided, and the design efficiency and performance of the functional asphalt mixture are improved. According to the method, the microstructure characteristics of the thermally recycled asphalt mixture are accurately quantified through the discrete element technology, the correlation model of the functional reinforced phase parameters and the skeleton gaps is established, the problems that a traditional test depends on experience and is low in efficiency are solved, and a high-performance material solution is provided for a functional asphalt pavement.

The invention discloses a loader load process prediction method based on MBD-DEM coupling simulation data driving, and is applied to the technical field of loader load prediction. Comprising the following steps: establishing a multi-rigid-body dynamic model of a loading machine working device; constructing a discrete element model of the material particles by adopting discrete element simulation software; mBD-DEM coupling is realized based on the multi-rigid-body dynamic model and the discrete element model; different working condition combinations are set, and load history data are obtained; preprocessing the load history data and the corresponding working condition data; constructing and training an LSTM neural network; and predicting the loading process of the loader based on the trained LSTM neural network. According to the method, the mechanical kinematics and dynamics characteristics of the loading machine working device and the discrete characteristics of materials can be considered at the same time, and the load prediction accuracy is improved.

The invention is suitable for the technical field of plant simulation modeling, and provides a corn ear general modeling method, which comprises the following steps: determining composition unit ball particles according to an ear structure; segmenting based on the shape and arrangement of the grains; obtaining morphological representation parameters and fitting a function relationship; geometric model parameters are calculated; universal modeling of the horse-tooth-shaped and fan-shaped grains is achieved; calculating the coordinates of spherical particles by adopting a combined ball method; filling the contour with spherical particles through rotation and translation transformation, and establishing a geometric model; and completing discrete element model construction in combination with mechanical model parameters. The method has the advantages of being high in universality, high in modeling precision, good in flexibility and the like, calculation and parameter calibration processes can be simplified, group model analysis is supported, and a reliable basis is provided for simulation of behaviors such as threshing and breaking of corn ears.

The invention discloses a cement stabilized macadam mesoscopic fracture parameter rapid inversion method, and the method achieves the multi-dimensional improvement of model scale selection, automatic data processing, machine learning model construction, parameter result optimization and the like through the construction of an inversion process of a discrete element model-XGBoost model-particle swarm optimization model frame. The inversion efficiency is improved; the time and energy consumed by repeated manual trial calculation are reduced; the multi-objective optimization advantage of a vectorization particle swarm optimization algorithm is fully utilized, and the vectorization particle swarm optimization algorithm is combined with an XGBoost model, so that the optimal solution of a target vector is realized; compared with a manual trial and error method, the method has the advantages that multi-dimensional targets can be optimized at the same time, so that a real test result is approached at the fastest efficiency, and the precision of the cement stabilized macadam microscopic fracture parameters is greatly improved.

The invention is suitable for the technical field of plant modeling analysis, and provides a wheat leaf universal modeling method, which comprises the following steps: selecting a plurality of leaves of four wheat varieties, and testing and analyzing geometrical shape and size parameters and randomness and correlation thereof; solving the coordinates of the particles forming the balls by adopting a ball filling arrangement mode to obtain a geometric model of the stalks and four geometric models in which the balls formed by the three veins and the five veins are arranged at intervals and tangentially; measuring and calibrating contact mechanical parameters and adhesive mechanical parameters between the blades and between the blades and the boundary; adding the parameters into a mechanical model; and inputting the obtained geometric model and mechanical model of the leaf into discrete element software to obtain a discrete element model of the wheat leaf. The method provides important data support for modeling of the wheat leaves and other long-strip-shaped materials, and can be applied to simulation analysis of the contact action of the leaves and agricultural machinery parts in the wheat harvesting process and other technical fields needing wheat leaf modeling.

The invention belongs to the related technical field of printing material mechanics research, and discloses a discrete element modeling method and system for the compaction behavior of a printing material, and the method comprises the steps: S1, building a discrete element model of the compaction behavior of the printing material, and determining to-be-optimized parameters in the model and the range of the to-be-optimized parameters; establishing an objective function according to a deviation between a numerical calculation result obtained by discrete element model simulation and a test measurement result; s2, establishing a distributed reinforcement learning model: designing a state space according to the target function value and each parameter, and setting a reward structure and an action space of each to-be-optimized parameter, the reward structure being a reciprocal of the target function value; and S3, parameter inversion is carried out through the distributed reinforcement learning model, each optimized parameter is obtained, and discrete element modeling is completed. According to the method, the model parameters are optimized and determined through parameter inversion in the discrete element model based on the distributed reinforcement learning algorithm, the speed and efficiency of parameter inversion are improved, and the parameter inversion is more accurate.

The application discloses a TBM cutter rock breaking efficiency optimization method and control system based on penetration and cutter spacing coupling, comprising: constructing a double-cutter rock breaking linear cutting numerical model, wherein the double-cutter rock breaking linear cutting numerical model is a discrete element model; simulating the double-cutter rock breaking linear cutting numerical model, and calculating the rock breaking specific energy consumption under the cutting action of different penetrations and cutter spacings according to the simulation result, wherein the rock breaking specific energy consumption is calculated according to mechanical parameters and lithology parameters; fitting the rock breaking specific energy consumption under different penetrations, and obtaining an optimal cutter spacing according to the fitting result, calculating the cutter spacing and penetration ratio according to the optimal cutter spacing; obtaining an optimal penetration and cutter spacing combination according to the trend of the cutter spacing and penetration ratio; and adjusting the penetration and cutter spacing of the TBM cutter according to the optimal penetration and cutter spacing combination, so as to improve the rock breaking efficiency and construction speed of the TBM.

The application discloses a soil deep loosening simulation method based on DEM-FEM bidirectional coupling. The method comprises the following steps: establishing a soil discrete element model and a deep loosening tool finite element model; using the discrete element DEM simulation to analyze the influence law of soil characteristic parameters and deep loosening tool motion parameters on soil deep loosening effect and deep loosening tool working resistance; changing the soil characteristic parameters and deep loosening tool motion parameters, and calculating the information such as soil deep loosening particle mixing degree, deep loosening tool working efficiency and working resistance under different variables; analyzing the influence law of the working resistance obtained from the DEM on the deep loosening tool structure through the finite element FEM analysis, changing the soil structure parameters and deep loosening tool structure parameters, and counting the statics and dynamics analysis results under different variables; simulating through the DEM-FEM bidirectional coupling, analyzing the soil deep loosening mechanism of the deep loosening tool, and obtaining the parameter and structure optimization results. Compared with the prior art, the application can effectively reduce resistance and consumption, and improve working efficiency.

The invention discloses an abrasive water jet rock breaking simulation method based on a DEM-CFD coupling method. Establishing an EBPM bonded rock mass discrete element model through a discrete element DEM, and calibrating mesoscopic parameters through a virtual mechanical test; simulating a water-abrasive two-phase flow through fluid dynamics CFD, and adopting a Gidaspow drag force model; the DEM-CFD bidirectional interface realizes real-time coupling; carrying out post-treatment to extract an erosion morphology and a crack network; the method can effectively simulate the rock mass fracture process and the large deformation behavior in the water jet rock breaking process and reveal rock mass damage evolution from the microscopic scale, and can be widely applied to research of water jet assisted rock breaking in the fields of civil engineering, mining, petroleum energy, marine resources and the like.

The application discloses a kind of discrete element modeling methods of multi-layer interpenetrating shear mixing drill and soil body, comprising: S1, the design parameter of multi-layer interpenetrating shear mixing drill is obtained, design parameter includes the pitch of blade, inclination, shape, size and quantity;Multi-layer interpenetrating shear mixing drill includes inner drill rod, multiple pairs of inner blades and outer frame arranged on inner drill rod;The outer frame includes multiple pairs of outer blades, two side plates and a collar arranged at intervals, and each pair of outer blades and each pair of inner blades are arranged at intervals;S2, the modeling of multi-layer interpenetrating shear mixing drill is carried out to obtain drill model;S3, establish soil model, import drill model, distribute contact model, and construct the coupling discrete element model between multi-layer interpenetrating shear mixing drill and soil particles;S4, simulation is carried out using coupling discrete element model, and quantitative analysis is carried out on mixing effect according to simulation result.The coupling discrete element model constructed by the above method has reliability and engineering applicability, and provides quantifiable basis for drill structure optimization.

The invention belongs to the technical field of lithium batteries, and relates to a material particle size grading optimization method and system based on a genetic algorithm and discrete element simulation. The method comprises the following steps: carrying out particle size distribution test on a material to be optimized to obtain a particle size distribution result as an optimizable particle size range; carrying out three-component peak separation on the obtained particle size distribution result, and approximately representing the particle size distribution of the material through three-component spherical particles; optimizing the stacking density of the three-component spherical particles in an optimizable particle size range by utilizing a genetic algorithm, and enabling the optimized stacking density of the three-component spherical particles to be approximate to the compaction density of the three-component spherical particles; obtaining physical property data of the material; and carrying out simulation verification on the compaction density of the three-component spherical particles obtained by optimization by using a discrete element model according to physical property data of a material. According to the method, optimization design is carried out on the particle size of the material based on discrete element analog simulation and a genetic optimization algorithm, and the large and small particle gradation of the high-compaction-density material can be rapidly screened.